Less than a month after the sudden death of award-winning film and TV scriptwriter Frank Deasy, it is becoming clear that he has left a legacy that will go far towards helping save hundreds of lives.

Figures released by the NHS Blood and Transplant authority to the Observer this weekend show that the "Frank Deasy effect" has resulted in a large leap in the numbers of people in Britain signing up to the online organ donor register.

Dublin-born Deasy died of liver cancer on 17 September, days after writing an article in the Observer to draw attention to the plight of hundreds of people like him, living on "an invisible death row" because of the shortage of organ donors. The 50-year-old father of three young children died on the operating table at Edinburgh's Royal Infirmary, but his candid humanity left its mark.

"I can't say all these registrations were directly attributable to Frank Deasy's appeal in the Observer, but it is likely that they were responsible for a large proportion," she said. "By 18 September we'd detected hundreds of registrations. By the following week, it had risen to thousands. The total of web and phone registrations for these two Sundays and Mondays came to 3,002, which was a tremendous tribute to Frank's appeal.

"The web and phone are the most immediate ways of joining the organ donor register and our best way of judging the effect of specific events or activity. But there are other channels – the tick boxes on the driving licence forms and applications to join a new GP – but it is less easy to analyse the effect of appeals on registrations through these routes." In Ireland, where Deasy went on a radio show to talk about his Observer article three days before he died, some 10,000 new donor cards were applied for. The Irish Kidney Association was inundated with calls and texts from people moved by Deasy's story and had to print thousands of extra cards to send to them.

To join the NHS Organ Donor Register, call the Donor Line on 0300 123 23 23, go online at www.organdonation.nhs.uk or text SAVE to 84118

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